SEMMPF3-031 Finishing materials by electroplating methods

Transcription

1 Overview This standard identifies the competencies you need to carry out electroplating processes to various substrates, in accordance with approved procedures. The electroplating activities carried out will include copper, gold, silver, platinum, cadmium and other specific processes. It does not cover nickel, zinc, alloy and chromium plating, for which other standards are available. You will be required to access the appropriate specifications, to check that these are of the latest issue and to extract all necessary information in order to carry out the electroplating operations. You will be required to carry out all necessary preparations to the base materials prior to plating them and this will include such items as cleaning, degreasing, masking and other appropriate treatments. You will be expected to prepare and adjust the plating solutions to give satisfactory deposits at optimum productivity levels. You will be expected to identify any plating defects, and to carry out the necessary actions and adjustments to equipment and plating solutions in order to correct them. You will need to carry out tests on the components to ensure that the deposited layers meet the specification requirements. Your responsibilities will require you to comply with organisational policy and procedures for the plating activities undertaken and to report any problems with these activities or with the materials and equipment used, that you cannot personally resolve, or are outside your permitted authority, to the relevant people. You will be expected to work with a minimum of supervision, taking personal responsibility for your own actions and for the quality and accuracy of the work that you carry out. Your underpinning knowledge will provide a good understanding of your work and will provide an informed approach to applying electroplating methods, techniques and procedures. You will understand the plating processes and their application and will know about them in adequate depth to provide a sound basis for carrying out the activities, correcting faults and ensuring the finished components are to the required specification. Your knowledge will also include effluent treatment for the waste streams from the plating solutions and associated processes. You will understand the safety precautions required when carrying out the preparation and electroplating operations. You will be required to demonstrate safe working practices throughout and will understand the responsibility you owe to yourself and others in the workplace and towards the environment. 1

2 Performance criteria You must be able to: P1 work safely at all times, complying with health and safety, environmental and other relevant regulations, directives and guidelines P2 ensure the material surfaces to be treated are suitably prepared for the finishing operations to be carried out P3 check that the finishing equipment and treatment solutions are set up and maintained at satisfactory operating conditions and levels P4 carry out the treatment process in accordance with operating procedures and the component specification requirements P5 ensure that the treated workpiece achieves the required characteristics and meets the finishing specification P6 deal promptly and effectively with problems within your control and report those that cannot be solved P7 dispose of waste and excess materials in line with agreed organisational procedures P8 shut down the finishing equipment to a safe condition on completion of the processing activities 2

3 Knowledge and understanding You need to know and understand: K1 the specific safety precautions to be taken when working with electroplating plant and solutions, and with associated pre-cleaning and post-treatment processes (to include specific legislation, local authority authorisation for the process, codes of practice and manufacturers' recommendations relating to the plating materials used and the method of application such as the use of air filtration equipment, effluent disposal, electrical supply, conductivity and earthing) K2 the actions to be taken in the event of suspected chemical poisoning K3 the environmental impact of the materials you are using and how to minimise this impact K4 the health and safety requirements of the work area in which you are carrying out the electroplating activities and the responsibility these requirements place upon you K5 the importance of extraction for acid pickling and for cyanide and alkaline plating solutions K6 the hazards associated with applying coatings using electroplating methods and with the materials and equipment used and how they can be minimised K7 the personal protective equipment (PPE) and clothing to be worn during the electroplating activity K8 the various types of specifications that are used during the electroplating activity K9 the assessment of the component to select its suitability for electroplating (to include suitable methods of handling, correct methods of pretreatment, the correct plating material to use, the most efficient and appropriate method of application) K10 the basic principles of operation of the electroplating equipment used K11 how to set up and check that the electroplating plant, equipment and solutions are fit for purpose K12 properties of electroplated deposits K13 the mechanisms of corrosion protection arising from an electroplated deposit as a surface layer K14 the properties of different passivation and the effects of sealants and torque control additives K15 how to decide whether components are suited to rack or barrel plating, jigging or wiring techniques K16 how to make up plating solutions, safely and correctly K17 how to identify various coating specifications K18 de-embrittlement and reactivation procedures K19 limitations of geometry and its effect on throwing power K20 how to test coated components for specification compliance 3

4 K21 how to identify processing faults, and how to correct them K22 visual assessment of workpieces for colour and brightness K23 how to control and assess brightener and other additive dosing rates K24 how to neutralise and precipitate out effluent waste streams K25 the benefits of agitation and the need to keep absorption of air into alkaline plating solutions to a minimum K26 the effects of contaminants in plating solutions and how to remove these K27 the extent of your own responsibility and whom you should report to if you have problems that you cannot resolve 4

5 Additional Information Scope/range related to performance criteria You must be able to: 1 carry out all the following during the electroplating process: 1.1 use the correct issue of process and other related specifications 1.2 use copies of relevant COSHH sheets, risk assessment and standards 1.3 ensure that the equipment is correctly prepared for the electroplating operations 1.4 wear appropriate protective clothing and equipment (PPE) at all times during the electroplating process 1.5 clean all tools and equipment on completion of the electroplating activities 1.6 complete the production documentation (such as condition/pretreatment of substrates, coating material preparation, equipment settings, confirmation of standard of finish) 1.7 leave the work area in a safe and clean condition 2 carry out two of the following plating processes: 2.1 copper 2.2 cadmium 2.3 gold 2.4 platinum 2.5 silver 2.6 other specific process 3 carry out the electroplating process on two of the following substrates: 3.1 mild steel 3.2 copper 3.3 stainless steel 3.4 zinc base die castings 3.5 plastics 3.6 brass 3.7 aluminium 3.8 other metals/substrates 4 measure and, where applicable, correct two of the following electroplating conditions: 4.1 levels of basic constituents 5

6 4.2 temperature 4.3 carbonate levels (where applicable) 4.4 plating efficiencies 4.5 contaminants in plating solutions 4.6 brightener dosing levels 4.7 current densities in the processes 4.8 processing and rinsing times 5 measure and where applicable, correct two of the following: 5.1 total and free alkalinity of cleaners 5.2 contamination levels in cleaners 5.3 effectiveness of inhibitor in acid pickling process or dry acid salt activator 5.4 effectiveness of rinsing 5.5 temperature of cleaners 6 carry out electroplating activities using one of the following types of electrolytes: 6.1 alkaline 6.2 neutral 6.3 acidic 7 prepare for the electroplating activities, by carrying out three of the following: 7.1 prepare new solutions from basic additives 7.2 make additions of basic constituents to existing plating solutions and associated processes 7.3 calculate the amount of brightener and other maintenance additions required 7.4 set ampere-hour or other automatic dosing equipment (where applicable) 7.5 dispose of process and other solutions in line with environmental and organisational procedures 7.6 clean out tanks 8 check plated components for two of the following: 8.1 throwing power of plating solution 8.2 levelling of the plated deposit 8.3 brightness of deposit 8.4 colour of the deposit 8.5 evidence of burning or poorly applied coatings 8.6 overall coverage 8.7 presence of blisters or nodules 6

7 9 use one of the following methods for locating the work during the electroplating process: 9.1 wiring 9.2 specialised jigs 9.3 jigs with integral masking 9.4 jigging components, which are masked prior to processing 9.5 barrels 9.6 reel-to-reel techniques 10 carry out one of the following quality control procedures: 10.1 thickness testing by micro sectioning 10.2 corrosion testing 10.3 thickness testing electromagnetic induction 10.4 adhesion of deposit 10.5 thickness testing eddy current permeability 10.6 brittleness of deposit 10.7 thickness testing X-ray fluorescence 10.8 torque tension testing 10.9 other specific method 11 ensure the electroplating complies with one of the following quality and accuracy standards: 11.1 Ministry of Defence (MoD) 11.2 BS/ISO or other international standards 11.3 AMS standards 11.4 company standards and requirements 11.5 customer standards and requirements 7

8 Developed by SEMTA Version number 2 Date approved February 2013 Indicative review date Validity Status Originating organisation Original URN Relevant occupations February 2018 Current Original SEMTA MPF3.31 Engineering and manufacturing technologies; Manufacturing technologies; Process, Plant and Machine Operatives; Process Operatives Suite Materials Processing and Finishing Suite 3 Key words Engineering; manufacturing; processing; finishing; electroplating; copper; gold; silver; platinum; cadmium 8